They're both facing little-known opponents who have echoed Trump's bombastic and controversial style and tried to latch onto the businessman's surprising success among Republican primary voters. Alan Grayson and Patrick Murphy - looked like it would turn into a proxy fight between progressive and centrist Democrats.
Rubio, however, has come out in support of Trump and even said that he would be willing to campaign alongside the billionaire businessman, telling CNN that the U.S. But according to polls, his message has failed to catch fire against Rubio's sky-high name recognition in the state.
"I can commit to you this", Rubio said.
Beruff has spent big, but the money and message have made little impact on the race.
Mr. Rubio's voting record in the Senate became an issue in the presidential, when Mr. Trump charged in a debate: "This guy has the No. 1 absentee record in the United States (Senate)". In Arizona, tea partier Kelli Ward has questioned the health and conservative credentials of the 80-year-old McCain, a two-time presidential candidate.
"Here's something he learned from earlier primary challenges, and that is to take them very, very seriously".
Millionaire homebuilder Carlos Beruff had rolled the dice to see if the anti-establishment mood powering Donald Trump's presidential campaign could send him to Washington as well.
Rubio made a last-minute decision to seek another term and almost cleared what was a crowded Republican field.
As much as one-third of Florida's congressional delegation could turn over this year over due to retirements, redistricting and resignations. Canova has raised about $3.3 million - more than Wasserman Schultz and an astounding amount for a first-time candidate running against someone who has served the area for more than 24 years in the state Legislature and Congress. Grayson, a three-term progressive firebrand, has faced accusations of domestic abuse and questions about running a hedge fund as a sitting member of Congress.
On the Democratic side, Murphy earned endorsements from the president and vice president, Senate Minority Leader Harry Reid, and the Democratic Senatorial Campaign Committee, all of whom saw him as a stronger general election candidate than the volatile Grayson. Rubio had no public events scheduled before polls closed, while Murphy began his day at 7 a.m.at a Miami-Dade polling site, joined by Gov.
Insiders are also keeping a close eye on Democratic primaries in the 5th district, where incumbent Corrine Brown is trying to overcome the twin obstacles of a major redistricting and a 22-count federal indictment; and in the 9th District, where Grayson's wife, Dena, is seeking to replace her husband. Bernie Sanders and many of his progressive supporters. But a narrow victory or surprise upset would be a clear sign that the frustration over the DNC's role in the presidential primary - and progressive dissatisfaction with the party establishment generally - have not ebbed since the primary.
Florida voters will select Tuesday the nominees for U.S. Senate, decide whether to amend the state constitution to give a property tax break to promote solar energy and have a say in who should represent them in the U.S. House.