Sen. Elizabeth Warren (D-Mass.) linked the Republican Party 's obstruction throughout President Barack Obama 's tenure to the rise of Donald Trump , arguing the GOP has only itself to blame for the state of the presidential race.

In an interview Thursday with MSNBC 's Rachel Maddow, Warren said the popularity of Trump and Sen. Ted Cruz (R-Texas) is simply a byproduct of seven years of a Republican Party that refused to treat Obama's presidency as legitimate.

"These are both people who basically deny the legitimacy of their opponents, they go on the attack, they demean millions of Americans," she said. "That's what identifies them as extremists."

But according to Warren, that brand of extremism is nothing new within the Republican Party.

"What have Republicans in the Senate been doing since the very day Barack Obama was sworn in?" Warren said. "They have given into their extremists. In fact, they have nursed their extremists along, so that there have been fights and delays over the basic things that happen in government."