Today in the Morning Line:

Stage set for Scott-Crist battle in Florida

A quick Florida history lesson

Ducey to face DuVal in race for Arizona governor

Obama administration building case for expanded action in Iraq, Syria

Matchup set in race for Florida governor: The results of Tuesday’s gubernatorial primary contests in Florida were never really in doubt, with Republican incumbent Rick Scott and Democratic challenger Charlie Crist having spent much of the past year focused on each other and not on their primary opponents. Crist, a former Republican governor, won his primary by nearly 50 points over former state Sen. Nan Rich, a tally that should quash any lingering questions about his level of support in his new party. Scott also scored a convincing victory, taking 88 percent of the GOP primary vote. The Miami Herald’s Marc Caputo notes that early returns showed Scott “won about 200,000 more votes in his under-the-radar primary than Crist and about 127,000 more Republicans voted statewide than Democrats.” Crist could face trouble in November if that enthusiasm gap persists. For now, most polls show a close race, with a slight edge to Scott.

A little Florida history lesson: If Charlie Crist wins the governorship — for the second time — this fall he would become the first governor in Florida history to ever win as a member of two different parties, NewsHour’s Andrew Troast and Dave Sloan report. Crist would also be only the second Florida governor in 117 years — and only the second since it achieved statehood — to serve two non-consecutive terms. Gov. William Bloxham served as governor from 1881 to 1885 and was later elected again 12 years later. (When Florida was a territory, Richard Keith Call served two non-consecutive terms from 1836 to 1839 and again from 1841 to 1844.) Crist, though, would not be the first party-switcher in state history to serve as governor. Three Florida governors before him actually switched parties before holding office, but none to the Democratic Party. Sidney Catts changed from the Democratic to the Prohibition Party, after a primary dispute in 1916; Claude Kirk Jr. went from Democrat to Republican during Richard Nixon’s first presidential bid in 1960 and was elected as Florida’s first Republican governor in 1966. Bob Martinez also began his career as a Democrat but switched affiliations while serving as the mayor of Tampa before successfully running for governor in 1986. By the way, another fun fact: A Crist win would make him the first Democratic governor in Florida in 15 years.

Elsewhere on Tuesday: In Arizona, state treasurer and former Cold Stone Creamery chief executive Doug Ducey won the Republican nomination for governor, besting five other candidates with 37 percent of the vote. Ducey received the support of national GOP figures such as former Alaska Gov. Sarah Palin and Texas Sen. Ted Cruz, while second place finisher Scott Smith, the former mayor of Mesa, had the backing of outgoing Republican Gov. Jan Brewer. Ducey will face Democrat Fred DuVal, a past president of the Arizona Board of Regents, who ran unopposed in his primary. Ducey enters the general election contest as the favorite, given the conservative leaning of the state.

Building the case for expanded action in Iraq, Syria: The New York Times reported Tuesday the Obama administration has started “to mobilize a broad coalition of allies behind potential American military action in Syria and is moving toward expanded airstrikes in northern Iraq.” That follows previous reports that the president had approved surveillance operations over Syria to gain additional intelligence about Islamic State militants there. “Rooting out a cancer like ISIL won’t be easy and it won’t be quick,” the president said Tuesday in a speech at the American Legion national convention in Charlotte. While the president said the U.S. would “continue to take direct action where needed to protect our people and to defend our homeland,” he also made clear he did not intend for the country “to be dragged back into another ground war in Iraq.” The situation underscores the pressures felt by a president who previously declared he was “elected to end wars, not start them.” Beyond determining the next steps in Iraq and Syria, the administration must also contend with political demands at home. On Tuesday, Sen. Tim Kaine, D-Va., said he does “not believe that our expanded military operations against ISIL are covered under existing authorizations from Congress.” For its part, the administration sees things differently, with White House press secretary Josh Earnest telling reporters Tuesday that the “current military action that has been ordered in Iraq is vested in the powers of the commander in chief.”

Daily Presidential Trivia: On this day in 1908, future President Lyndon Baines Johnson was born in central Texas. What was LBJ’s first job, before becoming a politician? Be the first to Tweet us the correct answer using #PoliticsTrivia and you’ll get a Morning Line shout-out. Congratulations to Rich Polanski (‏@ao2666) and Graham H. Morris (@GrahamHMorris) for guessing Tuesday’s trivia: Which president beat out Ted Kennedy in the Democratic primary the only time he ran for president? The answer was: Jimmy Carter.

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