Bernie Sanders and Hillary Clinton appear to have split victories in the Oregon and Kentucky primaries Tuesday night.

With all counties reporting in Kentucky, Clinton was leading Sanders by a narrow margin of 1,924 votes out of more than 450,000 cast. Secretary of State Alison Lundergan Grimes told CNN that Clinton was the "unofficial winner," but the Associated Press said the race was too close to call.

Sanders had a more comfortable victory in Oregon, where he was leading Clinton by more than 7 points. De facto GOP nominee Donald Trump, the only remaining candidate, easily won the state's Republican primary.

Ultimately, Tuesday's dueling victories did little to change the trajectory of the Democratic race. The two will end up splitting delegates in Kentucky, and Sanders will gain a handful more than Clinton in Oregon. But her delegate lead will still remain almost 280 pledged delegates — virtually impossible for Sanders to make up in the remaining six state contests.

Speaking at a rally in California late Tuesday, Sanders was defiant that he would remain in the race despite the "steep hill" he faced. He said he was confident he would win the state's primary on June 7 and promised to "fight for every vote" until the District of Columbia's Democratic primary on June 14, and "take our fight to the convention" in July in Philadelphia.

Clinton's apparent Kentucky win was her first primary victory since April; the Vermont senator recently notched wins in Indiana and West Virginia, but by margins that did little to close the gap with Clinton. Still, her repeated losses spurred talk that Clinton would have difficulty uniting Democrats in the fall, and also exposed her weaknesses with younger voters and white, working-class men. And it stalled her efforts to fully turn her attention to a likely general election matchup with Trump.

That Bluegrass State victory is one Clinton fought hard for, campaigning heavily in the state. According to NBC News, it was the first state since March 15 where she outspent Sanders on the airwaves.

Both the Kentucky and Oregon contests were closed primaries — meaning only registered Democrats — and not independents or crossover Republicans — could vote. Throughout the primaries, Clinton consistently has done better in such closed contests.

Sanders did well in Kentucky's more rural areas — coal mining-heavy regions similar to those he captured last week in the West Virginia primary. Those are areas Clinton did well in versus Barack Obama in 2008, but since then she has come under fire for comments suggesting she would begin to phase out the industry in favor of cleaner energy sources. She also has become aligned with President Obama's unpopular environmental policies in the region. But Clinton did well enough in metro areas of the state like Lexington and Louisville to take the lead over Sanders.

In Oregon, where votes were almost entirely cast by mail-in ballot, Sanders carried the state's progressive electorate and won by big margins in areas with college towns.

Kentucky's 55 pledged delegates will be split proportionally, and such a close finish means Clinton and Sanders each will get roughly the same number — again, not really enough to change Clinton's advantage over Sanders. He still needs to win about 66 percent of all remaining pledged delegates to hold a majority of them; when superdelegates are included, that proportion climbs to around 84 percent.

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