CNN  — 

Every congressional leader seeking majority support follows the mantra: “When you have the votes, vote.” The sentiment applies to presidential politics, too

That’s why President Donald Trump so strongly opposes easing voting procedures in response to fears of coronavirus this fall.

Poll after poll makes plain that, less than five months before Election Day, Trump lacks the support to win a second term.

Trump’s tweets slamming states for encouraging mail-in voting, his legal action to stop them, and his attempts to undermine public confidence with groundless “fraud” claims show that he knows higher turnout will work against him. So does his resistance to robust federal assistance to assure elections officials can adapt to the challenges the pandemic poses for November.

The question is whether Trump will be able to affect the election outcome. It won’t be easy, for three reasons.

The first is America’s federal system, which disperses responsibility for election supervision to state and local officials.

The second is the broadly-accepted, decades-long trend toward making voting easier.

Visit CNN’s Election Center for full coverage of the 2020 race

In 2016, just 60% of ballots were cast in-person on Election Day, while 40% were cast in advance by mail or at “early voting” sites. That is set to accelerate this year as more jurisdictions lift restrictions on absentee ballot requests, or in some cases move to make mail-in voting the default.

The third is the demonstrated propensity of voters to overcome obstacles if they believe political opponents seek to impede them. In Georgia, where Democrats have long accused Gov. Brian Kemp and other Republicans of “voter suppression,” the state’s primary election this month drew widespread news coverage for faulty voting equipment and long lines at a reduced number of polling sites. With a surge in mail voting, the primary ended up setting a Democratic turnout record.

Partisan challenges date back to the Civil War

Partisanship has colored changes in voting procedures throughout American history. Civil War Democrats resisted absentee ballots for Union soldiers in 1864 on grounds that improprieties would benefit Abraham Lincoln. World War II Republicans did the same 80 years later for fear it would boost Franklin D. Roosevelt. (Southern Democrats joined Republicans in resisting because they opposed enfranchising Black soldiers.)

Modern-day Republicans, overwhelmingly dependent on White votes, have advocated stricter screening procedures as America grows more diverse. They call steps such as requiring that voters show identification necessary to prevent fraud, despite scant evidence that significant election fraud takes place. Trump insists expanded mail voting would “rig” the election.

“Support for absentee voting has always been contingent on which political party thought it would advantage them,” observes Donald Inbody, a naval officer-turned-historian of voting by military personnel. “The Republicans have presumed that mail-in voting will negatively affect their candidates. It’s clear.”

The move to no-excuse mail-in voting

There’s actually no evidence mail voting disadvantages Republicans at all. Nor have partisan concerns halted the trend toward reforms to make voting more convenient.

Five states – Washington, Oregon, Hawaii, Colorado and Utah – had shifted to universal mail voting when the 2020 election cycle began. Another 29 plus the District of Columbia permitted any voter to request a mail ballot without specifying a reason.

Those “no excuse” absentee-voting states include all six top 2020 battlegrounds: Arizona, Florida, Michigan, North Carolina, Pennsylvania and Wisconsin. Since the pandemic hit, California and several other states have moved to expand mail balloting to spare more voters the risk of exposure from Election Day crowds.

There remain scores of procedural decisions between now and Election Day that could affect voting on the margins in various states. On mail, they include whether to spare voters the step of requesting a ballot and peremptorily send one, and whether to adjust verification requirements such as witness signatures as many Americans isolate to avoid infection.

The pandemic effect

State and local officials will also consider whether to expand early voting dates and locations, how to augment their election volunteer corps to make up for elderly regulars staying home because of vulnerability to coronavirus, and how to compensate for the closure of traditional sites such as retirement homes that have become hotspots.

“Elections officials were going to be stressed even before everything happened,” says Michael McDonald of the United States Elections Project.

After the immense voter surge in 2018, McDonald envisions “storm of the century” turnout of perhaps two-thirds of eligible voters. Partisanship looms over all those decisions. Four of the top six swing states have Democratic governors; all six have Republican-controlled legislatures.

In Washington, Trump and Republicans have blocked 90% of the $4 billion that Congressional Democrats seek for state and local governments to assure unimpeded voting. The President doesn’t hide his motivation, complaining the aid would produce “levels of voting that, if you ever agreed to it, you’d never have a Republican elected in this country again.”

His Democratic rival Joe Biden stokes Democratic determination by warning supporters Trump aims to “steal the election.” Led by top election lawyer Marc Elias, Democrats have filed more than 30 suits in 17 states to ease voting procedures.

McDonald sees mail ballots more than doubling to at least 50% of the vote in any case. The increase in volume will challenge the tabulation capacity of election supervisors.

Harvard elections scholar Alex Keyssar warns that Trump-friendly legislatures could seize on fraud claims to exercise their constitutional power to bypass voters and appoint representatives to the Electoral College themselves. More sanguine experts say Americans simply need to gird for a slow count.

“I do believe we will have a good election,” says Wendy Underhill of the National Conference of State Legislatures. “Whether we’ll have a result at midnight on Election Night, I can’t say.”