It wasn't supposed to take this long for Hillary Clinton to secure her Democratic Party's presidential nomination, but after five months of voting Bernie Sanders continues to stand in her way as the final primaries are held.
The pair will face off Tuesday in primaries in six states, including the biggest electoral prize of all - California.
The last states to vote will likely determine whether the Democrats can finally put the long nomination contest aside and turn to fight Republican Donald Trump or whether intra-party fighting will continue between Clinton and Sanders.
As of Friday, Clinton was just 71 delegates shy of nabbing the nomination and she is set to pick up more delegates in contests in the US territories of Puerto Rico and the Virgin Islands over the weekend. Sanders however hopes to keep Clinton from clinching the nomination outright and force the issue to be decided at the party convention in July.
One of the states to vote Tuesday - New Jersey, North and South Dakota, Montana, New Mexico and California - is likely to put Clinton over the top.
She has a strong lead in New Jersey, which has 142 delegates, with an average of opinion polls giving her a 17 percentage point lead. The eastern state will be the first to close its polls Tuesday and could give her the nomination.
But Sanders has pinned his hopes on California, the country's largest state and a major delegate prize with 546.
"California is the big enchilada, so to speak. Obviously, it is enormously important and obviously, we want to win it," Sanders told broadcaster NBC and vowed to "fight until the last vote is cast."
Sanders has been criss-crossing California and on Wednesday spoke to a cheering crowd in Palo Alto held on a sports field in the heart of Silicon Valley.
The crowd waited under the hot sun for three hours, to listen to Bernie hit on subjects like immigration, the environment, social justice and education.
"California is last in the primary game and we usually feel like our votes don't matter. But now it's a different feel. We have a voice in the nomination process and we go out in full force for Bernie," supporter Leila Garlinghouse told dpa.
An average of opinion polls by website Real Clear Politics show Clinton with a lead of 4.7 percentage points over Sanders in the state. But Sanders has been narrowing the gap. A University of Southern California and Los Angeles Times poll released Thursday put them in a statistical dead heat.
"Bernie Sanders has tapped into a wellspring of support in the Democratic primary over the last several weeks and he’s closing with a rush," said Dan Schnur, director of the university's Institute of Politics.
It will come down to turnout with Sanders needing to bring out many supporters who are young and new to politics, while Clinton would benefit from traditional party loyalists who are more likely to vote, Schnur said.
Even if Sanders were to win California, he would still trail Clinton in the delegate total and then hopes to make the case to the party officials who serve as so-called superdelegates that he is the best choice to face Trump.
Clinton currently has 2,312 total delegates to Sanders' 1,545, with 2,383 needed to win, according to The New York Times.
But her lead is narrower without the superdelegates, who can support whomever they choose and now overwhelmingly back Clinton. Clinton has 1,769 pledged delegates who must back her and Sanders has 1,501.
If Sanders wins California, it could prompt a rethinking of whether Clinton is best positioned to take on Trump in November and cause a major re-evaluation within the party, Democratic pollster Douglas Schoen warned in the Wall Street Journal this week.
On the Republican side, Trump is the presumptive nominee after his competitors left the race and he secured the delegates needed to win the party's nomination last month with the declared support of unbound delegates.
Most delegates are awarded as a result of state primary votes and are pledged to the winners of those contests. Trump has 1,150 of those pledged delegates.
He will clearly surpass the 1,237 delegates needed, even without unbound delegates, in the party's final five primaries Tuesday.