Florida, Arizona and Oklahoma primaries 2018: Who are the candidates?

Everything you need to know as voters choose their preferred Republican and Democratic gubernatorial and senate candidates ahead of November's midterms

Republican gubernatorial candidate Ron DeSantis, left, listens to opponent Adam Putnam during a debate in Jacksonville (John Raoux/AP)

Voters are going to the polls today in Florida, Arizona and Oklahoma for the 2018 primary elections.

The primaries will see the electorate choose their preferred Republican and Democratic gubernatorial and senate candidates ahead of November's midterms.

Here's everything you need to know.

Florida

In the race to replace the Sunshine State's outgoing two-term governor Rick Scott – now running for the Senate and expected to secure his place alongside the Democrat's Bill Nelson with ease – the Republican candidates are Ron DeSantis and Adam Putnam.

Three-term congressman Mr DeSantis is president Donald Trump's choice and is expected to win the day with that endorsement. He recently launched a campaign ad in which he urged his toddler daughter to "build that wall" with toy blocks, referring to the president's plan to build a wall with Mexico.

But Mr Putnam, state agriculture commissioner, has used the presidential nod to his advantage, portraying his opponent as little more than a Trump stooge as part of his appeal to the party's establishment.

A late poll conducted by Florida Politics puts Mr DeSantis in the lead with 57 per cent to Mr Putnam's 33 per cent, with 10 per cent refusing to commit.

Among the Democrats, Gwen Graham, a former member of Congress and daughter of governor and senator Bob Graham, leads the field and is expected to win.

Her rivals for the nomination include Tallahassee mayor Andrew Gillum, a left-leaning favourite of Bernie Sanders, could make a late surge, while former Miami Beach mayor Philip Levine and Palm Beach businessman Jeff Greene have their fans and have significant financial backing. Orlando entrepreneur Chris King is also in contention.

Florida Politics polling puts Ms Graham ahead with 32 per cent of the vote, Mr Gillum on 25 per cent, Mr Levine on 22 per cent, Mr Greene on 10 per cent and Mr King on 2 per cent. Nine per cent were undecided.

The anticipated winners will be Mr DeSantis and Ms Graham and the subsequent race is expected to be extremely close.

The vote comes just days after the latest mass shooting, at a video game tournament in Jacksonville, which could potentially impact upon voters at the ballot box, with Democratic candidates speaking out passionately against gun ownership laws.

Arizona

In Arizona, a Senate primary will see three senior Republicans bid to replace Jeff Flake, not seeking re-election: America's first female combat pilot Martha McSally, Dr Kelli Ward and controversial former Maricopa County Sheriff Joe Arpaio, pardoned by President Trump over a contempt of court conviction.

The contest has been overshadowed in recent days by the death on Saturday of John McCain, Arizona's longtime Republican senator.

All three Republicans had distanced themselves from Mr McCain, who frequently feuded with Trump, and Ward suggested that his announcement before his death that he was stopping medical treatment was timed to hurt her campaign.

Mr Trump has not endorsed a candidate and Ms McSally, the favourite, has faced questions over her loyalty to his cause.

The Democratic candidates are former Green Party activist Kysten Sinema and attorney Deedra Abboud, the former far better known, widely expected to win and expected to provide tough competition for the eventual Republican winner.

Meanwhile, in the competition for state governor, the Republican incumbent Doug Ducey is facing a challenge from his own side in Arizona's former secretary of state, Ken Bennett.

Their Democratic rivals are David Garcia, a former Department of Education official, state senator Steve Farley and YMCA CEO Kelly Fryer.

Mr Ducey is expected to see off his Republican challenger while Mr Garcia is broadly expected to win out among the Democrats and would represent a progressive choice, backing universal healthcare and campaign finance reform.

Oklahoma

Oklahoma will see Republicans Mick Cornett and Kevin Stitt enter a run-off for the nomination to challenge Democrat Drew Edmondson for state governor, the latter securing his place in June, having previously run unsuccessfully in 2010.

Mr Cornett is Oklahoma City mayor while Mr Stitt is a Tulsa businessman offering himself as an outsider to the party establishment.

The two have already been chosen among 10 candidates to replace Mary Fallin, whose term of office has expired and who was widely unpopular after mishandling the state budget, resulting in cuts to public school funding and a round of teacher's strikes.