The former Florida governor, widely expected to run for the GOP nomination, tweeted "coming soon" with a link to the website jebannouncement.com. On that page, the date 06.15.15 was listed, followed by the tease, "BE THE FIRST TO KNOW. RSVP NOW!" Visitors to the site could enter their name and email address. Bush also tweeted it in Spanish, "Proximamente 6.15.15."

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Bush would enter a crowded primary that includes Sens. Rand Paul, Marco Rubio and Ted Cruz, among others. Former Texas Gov. Rick Perry is expected to announce his bid on Thursday.