WASHINGTON, United States (AFP) — Nancy Pelosi and Mitch McConnell are once-in-a-generation Washington lawmakers at the apex of their powers — and to a significant degree they are shaping the fate of US President Donald Trump.

Both in their late seventies and born 23 months apart, the two rivals are masters of the American political game, an odd couple rising to paramount positions in Congress on the strength of political savvy, grit and determination.

Speaker of the House Pelosi is calm, cool under pressure and tough as nails, the top Democrat in Congress and Trump’s chief nemesis who has guided her chamber — often with rival Republicans kicking and screaming — through the divisive impeachment inquiry investigating presidential wrongdoing.

This icon of American female power is virtually certain to keep her party together enough to get impeachment over the line this week in a bid to hold Trump accountable and build on her already substantial legacy.

On the opposite end of the US Capitol, the perpetually unruffled Senate majority leader with the soft Kentucky drawl has emerged as the chief Trump loyalist.

For years McConnell has used his procedural wizardry to tie Democrats in knots and ram through his party’s agenda — or block the priorities of his rivals.

All signs suggest the backroom commandant will order his Republican Party footsoldiers to hold the line in a likely Senate impeachment trial and help Trump avoid punishment.

“I’m not an impartial juror,” McConnell told reporters Tuesday. “This is a political process, there’s not anything judicial about it.”

Pelosi was first elected to Congress in 1987 and has been a thorn in Trump’s side since his inauguration, but particularly after she reclaimed the speaker’s gavel last January.

McConnell entered the Senate in 1984 and remains a potent force, employing a cold-blooded political calculation that has helped him thrive.