Dole's support gives the GOP presumptive nominee the support of another party elder on a day when other top Republicans announced their opposition. Trump inconspicuously announced the endorsement earlier on Friday at a rally in Omaha, Nebraska, as he ticked off the names of several prominent Republicans who have come around to his candidacy since he became the party's presumptive nominee earlier this week.
"The voters of our country have turned out in record numbers to support Mr. Trump. It is important that their votes be honored and it is time that we support the party's presumptive nominee, Donald J. Trump," Dole said in a statement released by Trump's campaign. "I plan to attend the RNC convention in Cleveland to show my support for our party and our ticket, as I have done my entire life. We must unite as a party to defeat Hillary Clinton."
In the same statement, Trump thanked Dole and said "he is a wonderful man and it is a great honor to have his support."
Earlier Friday, former Vice President Dick Cheney endorsed
Trump, while former 2016 candidates Jeb Bush
and Lindsey Graham
said they wouldn't vote in the election, part of a growing rift in the party over Trump's emergence as the Republican standard-bearer.
Dole had previously endorsed
Bush and subsequently backed
Florida Sen. Marco Rubio in the GOP primary, but was not as critical of Trump as many establishment Republicans had been throughout the divisive primary.
The former Kansas senator, who railed against the candidacy of Sen. Ted Cruz as too extreme, suggested
in an interview with The New York Times in January that he could come around to a Trump candidacy.
Dole said Trump could "probably work with Congress, because he's, you know, he's got the right personality and he's kind of a deal-maker."
Dole is the latest in a string of establishment Republicans who have warmed to Trump's candidacy since Trump's last two rivals, Cruz and Ohio Gov. John Kasich, dropped out of the race this week.
Dole is the second former Republican nominee to say he would support Trump. Sen. John McCain, the party's 2008 nominee, said this week he would -- albeit not with a full-throated endorsement -- support
Others have not been so quick to rally around Trump's candidacy.
Mitt Romney, the 2012 Republican nominee, said that he would not back Trump in the 2016 presidential election. The past two Republican presidents, George H.W. Bush and George W. Bush are planning to keep their voices out of the 2016 race.