Raising the federal minimum wage has been a Democratic priority for years, and Democrats now control the White House and Congress for the first time in a decade. So now might seem like the time.

But there are still barriers to the Democrats’ preferred option, a $15 minimum wage that would phase in over four or five years. Sen. Bernie Sanders (I., Vt.), who’s taking over as chair of the Senate Budget Committee, has pushed for a $15 wage for at least six years, and President Biden now endorses that. The minimum wage has been stuck at $7.25 since 2009, and it has generally declined relative to inflation for the last 50 years.

Biden wants a $15 minimum wage included in the $1.9 trillion relief bill Congress is drafting, which seems likely to pass by March. There are plenty of Congressional Democrats who support it. But a few Democrats don’t, and that’s probably enough to prevent the $15 minimum wage from passing.

Democrats control the Senate with the narrowest possible majority: a 50-50 split, with Vice President Kamala Harris casting the tie-breaking vote in favor of Dems. Republicans typically oppose a minimum-wage hike en masse, which means it would take every single Senate Democrat to vote for $15.

One Democrat says he won’t— Sen. Joe Manchin of West Virginia. But Manchin says he’d support raising the federal minimum wage to $11, which would still be 52% higher than the current level. West Virginia is one of the lowest-wage states, which means a sharp hike in the federal minimum would hurt employers more than it would hurt businesses in higher-wage states. That’s one of the problems with a federal minimum wage: it doesn’t account for the wide variation in living costs among states.

West Virginia is one of 28 states with a higher minimum wage than the federal standard – $8.75. So an $11 wage might not be that hard for employers to absorb, especially if it were phased in over time. It’s also possible Congress could pass a minimum wage hike this year but delay its implementation until GDP or overall employment have recovered to pre-pandemic levels, so as not to slow hiring as millions of unemployed Americans are trying to get back to work.

Manchin isn’t the lone spoiler on the $15 minimum wage. Five other Democratic senators declined to sponsor a $15 minimum wage bill Bernie Sanders and other Democrats introduced in January. Those five haven’t spelled out their stance the way Manchin has, however, perhaps because they’re reluctant to alienate voters who want a higher wage. Manchin, may have less to fear, as a Democrat representing a relatively conservative state.