Leaders Barcelona followed up Saturday's 2-0 victory over Real with a 3-0 home win against Deportivo La Coruna on Wednesday to go six points clear on 83 but Real's success in Andalucia has trimmed the gap back to three with six games left.
Almeria came under some early pressure at their Juegos Mediterraneos stadium before an unmarked Albert Crusat gave the home side a surprise lead in the 14th minute, sweeping a low Kalu Uche cross past Real goalkeeper Iker Casillas.
World Cup-bound Portugal forward Ronaldo sliced through the home defence to level with an angled shot in the 27th and Real squandered several chances to grab the lead before half time.
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Midfielder Guti struck a powerful drive against the post on the half hour and Argentina striker Gonzalo Higuain had an effort cleared off the line before Van der Vaart lashed home from just outside the penalty area in the 69th.
"We still have a chance to win the league but we have to win all our remaining matches," the Netherlands midfielder, who will be a key member of the Dutch team at the World Cup, said in a pitch-side television interview.
"I had a lot of chances and missed two or three in the first half so I'm very happy with the goal," he added.
GOOD RESPONSE
Real are out of the Champions League and the King's Cup and remain in danger of ending the season without any silverware despite an investment of close to a quarter of a billion euros in players for this season.
President Florentino Perez spent a record 94 million euros to buy Ronaldo from Manchester United and the 25-year-old's goal against Almeria was his 19th in the league this season, eight short of Barca's La Liga top scorer Lionel Messi on 27.
"At the start we were a bit flat because of what happened on Saturday (against Barcelona) but then we got into the match very well and created a lot of chances," Ronaldo told reporters.
"We didn't play a fantastic match but we managed to win and that's the important thing."
Barca, the Spanish and European champions, can stretch their La Liga lead back to six points with a win at city rivals Espanyol on Saturday and play the first leg of their Champions League semi-final at Inter Milan on Tuesday.
Real host third-placed Valencia on Sunday, with Unai Emery's side a massive 21 points behind them after their 2-0 home win over Athletic Bilbao in Thursday's late kick-off.
Spain midfielder David Silva struck either side of halftime at the Mestalla to lift Valencia seven points clear of fourth-placed Real Mallorca, who drew 1-1 at relegation threatened Real Zaragoza on Wednesday.
