From The Morning Grind

A brutal primary battle for the Republican Senate nomination comes to an end today in Tennessee, as voters head to the polls to choose their candidates for November. Two former congressmen and a former Chattanooga mayor are competing for the GOP Senate nomination to take on the likely Democratic nominee, Rep. Harold Ford, Jr.

The race to replace Senate Majority Leader Bill Frist (R-Tennessee), who is retiring and considering a run for president, has taken on national implications as Democrats would need to win this seat and five others to wrest control of the Senate from Republican hands.

"To take control of the Senate (Democrats) have to run the table which includes picking up this Republican leaning open state," said Amy Walter, senior editor of the non-partisan Cook Political Report. "If we think about the ability of the Democrats to take control of the Senate they can't do that just by beating a couple of incumbents."

For Republicans, there are concerns that this bruising Republican primary could leave the winner weakened heading into the general election. Each of the candidates aired negative ads and former Reps. Ed Bryant and Van Hilleary have questioned former Chattanooga Mayor Bob Corker's conservative credentials. Corker is the favorite to win the nomination, but as is in any campaign turnout is the key and Van Hilleary or Bryant could emerge as the winner at the end of the day.

So far, more than $5 million has been spent by the three Republicans and Ford on television advertisements, with Corker accounting for them than $3.2 million. Bryant has spent about $700,000, Van Hilleary about $600,000 and Ford a little more than $800,000.

Evan Tracey of TNSMI/Campaign Media Analysis Group, CNN's consultant on television advertising spending, suggested that Corker's advertising dollars have been well spent.

"Corker's spending advantage is paying off in the polls," Tracey said. "If he wins, however, he'll have some repair work to do because Van Hilleary and Ed Bryant have spent the last 30 days attacking Coker's character and record on core conservative issues like immigration and abortion. Ford has had a free run thus far and has spent wisely of issue in the news like energy prices and port security."

Ford's decision to run for Senate has created very crowded Democratic and Republican contests to fill this Memphis based House seat.