Barack Obama is about to launch a presidential campaign blitz for Hillary Clinton unprecedented in the modern era, pledging a dramatic commitment of time and resources to a contest he now unabashedly frames as a referendum on his personal and political prestige.

Obama plans to devote at least one to two days each week in October to campaign for Clinton through rallies, targeted radio and television interviews, social media outreach and fundraising, said an adviser who requested anonymity.

In addition, the president’s aides have told the Clinton campaign he would be willing to appear in television ads for her. His wife, Michelle, has already cut radio, online and TV ads for the Democratic nominee, another aide said, also requesting anonymity to discuss internal planning.

Obama’s involvement comes at a critical time, with enthusiasm for Clinton lagging behind support for Obama among the young people and minorities who helped power him to the presidency. At the start of the campaign, Clinton’s camp once questioned how closely to embrace Obama but now her aides are eager to have his help.