According to a list of Supreme Court nominations on the U.S. Senate's website, three presidents did not nominate any justices to serve on the nation's high court: Jimmy Carter, Zachary Taylor and William Henry Harrison.
Trump said Friday that his Supreme Court selection process would begin in earnest Monday and that he would interview "six or seven" candidates in total.
Kennedy has mainly supported abortion rights in his time on the court, and Trump has made clear he would try to choose justices who want to overturn the landmark abortion rights case of Roe v. Wade.
Although Kennedy was a conservative nominated by Republican President Ronald Reagan, he was seen as the "swing vote" on the court because he joined with liberal justices on some major issues, including expanding gay rights and upholding abortion rights.
Speaking on the Senate floor shortly after Kennedy announced his retirement, McConnell said he intends to vote on the nomination this year.
The Senate is bracing for Trump to announce a quick nominee as soon as July 10.
He was among several senators who met Thursday with Trump at the White House. Dean Heller in Nevada, a state that voted for Hillary Clinton in 2016, cast the fight as key to the "future of the Supreme Court" and knocked Heller as nothing more than a "rubber stamp" for Trump who could "jeopardize Roe v. Wade".
"Any Democrat who votes for Trump's nominee (assuming it's someone from his list of 25) will be voting to overturn Roe v. Wade".
Trump told Fox Business Network this week that he would probably not ask the question of potential nominees.
Sen. Cory Booker pledged a long-term battle to prevent Trump from rushing a conservative judge onto the court, even as he acknowledged it will be hard for Democrats to block any nominee since Republicans control the Senate. If Trump picks not one, but two reliable conservative justices, he will secure the best record of Supreme Court appointments by any modern Republican president.
"We have to pick a great one", Trump said. "I am not going to vote for anyone who tells me they are going to decide a case before the facts are presented".
Hawkins said her group has more than 1,200 chapters around the country, and organizers will encourage members to lobby their senators during the confirmation process. The 53-year-old appeals court judge is a former clerk for Justice Kennedy.
"They're looking for anything and everything to motivate their base because they know they've got a big problem on their hands", said Maslin. Democrats Joe Manchin of West Virginia and Heidi Heitkamp of North Dakota also talked to Trump.
Steven Law, president of the Senate Leadership Fund, a campaign group aligned with McConnell, said the group is running digital ads in 10 states that Trump won in 2016 where Democratic senators are now up for re-election.
"This Supreme Court vacancy puts issues that affect every single American in the balance, from a woman's constitutionally protected right to make her own health care decisions to privacy, equality and civil rights", Harris tweeted.
Instead, the choice of the next Supreme Court justice is in President Trump's hands.
A flashpoint in the court debate will be abortion rights, which puts a spotlight on key female Republican senators - Susan Collins, of ME, and Lisa Murkowski, of Alaska.
"It is exciting though, right?" said Trump.