Musicians John Mayer and Jessica Simpson are now officially an item. People magazine is reporting that Simpson is head over heels for Mayer. Simpsons pooch Daisy gave her approval as well.

So how did the opposites-attract pairing – the music-industry equivalent of the head cheerleader hooking up with the sweetly geeky drum major – happen in the first place? After meeting at Clive Davis’s pre-Grammy party in 2005 – when Simpson was still married to Nick Lachey, 32 – the couple “bumped into each other” in June at New York City nightclub the Double Seven, where a source says Simpson was “flirting up a storm” with both Mayer and actor Jared Leto. The singer was especially smitten when Mayer praised her new single, “A Public Affair.” “He flattered her,” says another source.

“I feel good being married to myself right now,” sources close to her say she is savoring the new romance. “They’ve barbecued at her house,” says a Simpson insider. “She’s just started gardening, and he impressed her by knowing all the flowers she planted.” Mayer is also “the antithesis of Nick,” says the source. “He makes her feel special and beautiful and smart. Nick used to laugh when she said something that didn’t sound smart.”